1. Field of the Invention
The present invention relates to blocking for use in roof systems and, more particularly, to a combined edge closure and cant strip formed as one-piece from a non-corrosive, durable material, such as galvanized steel, steel, aluminum or plastic and including a lower anchoring flange for attachment to the roof structure, a central portion including vent means formed therein, an upper flange, and a cant strip angled upwardly from the upper flange.
2. Description of the Related Art
Generally, roof systems used on most building structures, and particularly commercial buildings, require some type of blocking to provide a base for the attachment of roofing components such as, but not limited to, gravel stops, eves, drips, fascia, gutters, vent stacks, roof top equipment, expansion joints, roof curbs, copings and cant strips. Traditionally, wood is used for roof blocking and typically consists of one or more stacked wood boards (e.g., 2 inch by 4 inch or 2 inch by 6 inch boards) which are nailed to the roof structure and each other to provide a built-up base at various locations on the roof system wherein it is necessary to mount the roofing components and equipment. Presently, wood blocking is used on virtually all roof systems which require blocking for the purposes described above.
Despite its widespread use in roof systems, there are significant drawbacks and shortcomings associated with the use of conventional wood blocking. In particular, wood is susceptible to damage and deterioration from moisture, termites, ants, and other natural enemies. Further, because wood is a solid material, it does not provide for venting capabilities to permit escape of moisture and gasses from within the roof. The lack of adequate venting is a contributing factor of premature roof failure. Additionally, wood has limited pull-out characteristics for holding nails and other fasteners, thereby requiring a considerable amount of hardware to attach roofing components. Wood, being a natural product, is also prone to irregularities such as areas of reduced dimension, warping, and splintering. This makes it difficult, if not impossible, to achieve a straight, uniform blocking configuration. Furthermore, the dimensions of wood are limited to lumber industry standards which often does not correspond to the dimensions of roofing components, such as roof insulation or lightweight concrete thickness, expansion joint heights and equipment sizes.
In view of the shortcomings of traditional wood blocking used in roof systems, as set forth above, there exists an urgent need in the construction industry for an alternative blocking structure which overcomes the above-described problems. More specifically, there is a need for a combined edge closure and cant strip which provides for uniform dimensions in accordance with desired size and configuration specifications and which further provides for venting of the roof system. Additionally, there is a need for a one-piece, non-corrosive edge closure and cant strip which significantly reduces costs for labor and materials associated with the installation of a roof system.
The present invention is directed to a one-piece, integral structure formed from a non-corrosive material to replace traditional wood cant strips and edge closures which are currently used in roof systems of building structures.
The combined edge closure and cant strip is formed from a single sheet of non-corrosive material, such as galvanized steel, steel, aluminum or plastic and includes an anchoring flange, an upper flange, an intermediate panel, a cant panel and a mounting strip. The anchoring flange is structured and disposed for mating attachment to the roof structure underlying an insulation layer or lightweight concrete layer on the roof system. The intermediate panel extends upwardly from the anchoring flange to the upper flange, forming a gap or area of depth between the anchoring flange and upper flange. The gap is specifically adapted for receiving a predetermined thickness of insulation or lightweight concrete. The upper flange extends outwardly and generally perpendicular to the intermediate panel. The cant panel is angled inwardly and upwardly from the upper flange to a top mounting strip which is adapted to be secured to a concrete parapet or adjoining vertical wall on a roof structure. Vent means are provided in the intermediate panel to allow escape of moisture and gasses which otherwise remain trapped within the roof system. This helps to reduce the likelihood of premature roof failure, and thereby extends the life of the roof system.
With the foregoing in mind, the present invention has the following objects and advantages over the conventional wood blocking structures presently used in most roof systems.
It is a primary object of the present invention is to provide a blocking assembly for roof systems comprising one or more pre-formed components manufactured from galvanized steel, steel, aluminum, plastic or other corrosion-resistant materials to thereby provide resistance to deterioration from moisture, insects, warping, and the like.
It is a further object of the present invention to provide a blocking assembly comprising a one-piece structure forming a combined edge closure and cant for use in a roof system.
It is still a further object of the present invention to provide a blocking assembly having a pullout resistance which is significantly greater than that of wood, thereby requiring less hardware, labor and materials to install the blocking and attached roofing materials.
It is yet a further object of the present invention to provide a blocking assembly which is pre-formed and fabricated to conform to any roof insulation or lightweight concrete thickness requirements.
It is still a further object of the present invention to provide a blocking assembly for roof systems which includes venting means for allowing moisture and gasses to be released from the roof assembly, thereby reducing the likelihood of premature roof failure.
It is still a further object of the present invention to provide a blocking assembly for roof systems which is structured to encapsulate the edge of insulation and/or lightweight concrete.
It is yet a further object of the present invention to provide a blocking assembly having pre-punched fastener holes to thereby alleviate human error during installation.
It is still a further object of the present invention to provide a blocking assembly for roof systems which, once installed, becomes integrated with the roof structure.
It is still a further object of the present invention to provide a cant for roof construction which replaces traditional wood cants and which reduces the amount of materials needed in the construction of a roof system, thereby increasing efficiency of installation and reducing the overall cost of labor and materials.
It is still a further object of the present invention to provide a combined edge closure and cant for roof systems which replaces wood materials ordinarily used for such purposes and which is relatively inexpensive to manufacture.